In a failed attempt to reach a deal that would have restored its status as the world’s largest pharmaceutical company, biotechnology giant Pfizer Inc. – whose five-facility La Jolla site specializes in the manufacture of cancer drugs – has been turned down in what it terms its final offer to acquire AstraZeneca.

On Sunday, May 18, the British pharmaceutical giant rejected Pfizer’s $119 billion offer, potentially saving research posts at the La Jolla facility.

“Pfizer has a history of shutting down facilities,” said Raghuran Selvaraju, an analyst with Aegis Capital. “They don't thin down head count; they shut down an entire facility and pick up their stakes and move away.”

Pfizer's 25-acre La Jolla campus, on Science Center Drive near the I-5 and Sorrento Valley Highway intersection, includes five buildings totaling more than 500,000 square feet. The company spent $5.7 billion on research and development in 2013, down from $7.48 billion in 2012.

Pfizer would not disclose how many people work at the La Jolla facilities or other U.S. research centers.